This is a scientific study to determine expression of vascular adhesion protein 1 (VAP-1) in cancer patients by 68Ga-DOTA-Siglec-9 positron emission tomography/computed tomography (PET/CT) before and after cancer treatment.

The purpose of this study is to evaluate expression of vascular adhesion protein 1 (VAP-1) in bone marrow and cancerous lesions before and after therapy using 68Ga-DOTA-Siglec-9 positron emission tomography/computed tomography (PET/CT). Patients with acute myeloid leukemia (AML) that undergo bone marrow transplantation and patients with melanoma and lung cancer that undergo chemotherapy will be studied. In addition, imaging results will be compared with clinical data and research data from blood samples. The study is of great clinical importance as other methods do not provide such comprehensive information on the presence of the VAP-1 molecule in the body, especially in the bone marrow and cancer tissue before and after cancer treatment. Research is also important for drug development targeting VAP-1.

Inclusion Criteria:

• Diagnosis of acute myeloid leukemia (AML) and fit for allogeneic hematopoietic stem cell transplantation (alloHSCT), as assessed in the standard operating procedures.
• Diagnosis of metastatic melanoma and fit for immune checkpoint inhibitors or BRAF- and MEK inhibitors.
• Diagnosis of metastatic non-small cell lung cancer (NSCLC) (stage IV) and fit for immune checkpoint inhibitors and/or chemotherapy.
• Able and willing to give written informed consent and to comply with the study protocol.

Exclusion Criteria:

• Unsuitable for alloHSCT (AML), checkpoint inhibitors or BRAF- and MEK inhibitors (melanoma or checkpoint inhibitors and/or chemotherapy (NSCLC) according to the standard operating procedures.
• Unable or unwilling to comply with the study protocol for any reason.
• Evidence of significant uncontrolled concomitant diseases such as neurological, renal, hepatic, endocrine, or gastrointestinal disorders which, in the opinion of the Investigator, would preclude patient participation

Patients of Turku University Hospital with acute myeloid leukemia (AML), metastatic melanoma and metastatic non-small cell lung cancer (NSCLC) (stage IV)